Battle of the Marshes
1984 CE.
Shown on the map at 31.542°, 47.707°.
The Battle of the Marshes (Arabic: معركة الأهوار) was a part of the Iran–Iraq War. After the mostly indecisive Dawn operations in 1983, Iran opened a new, surprise amphibious offensive in the lakes of the Hawizeh Marshes in the Iraqi Tigris–Euphrates river system. After heavy losses at the beginning due to human wave attacks, 15,000 casualties and little progress, Iran began developing new tactics, involving amphibious assault, and deployed a regular army division, the 92nd Armored Division. Although the Iranians suffered heavy losses against the Iraqi artillery, tanks, air strikes and gunboats, Iran eventually managed to invade the oil rich Majnoun Islands with Operation Kheibar and nearly break the Iraqi lines before being driven back to the marshes and Majnoon Island. Iraq heavily used chemical weapons (mustard gas) during the battle.
Text from the Wikipedia article Battle of the Marshes, licensed CC BY-SA 4.0.